| Message ID | 20230903170736.513347-14-dmitry.osipenko@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add generic memory shrinker to VirtIO-GPU and Panfrost DRM drivers | expand |
On Sun, 3 Sep 2023 20:07:29 +0300 Dmitry Osipenko <dmitry.osipenko@collabora.com> wrote: > The vmapped pages shall be pinned in memory and previously get/put_pages() > were implicitly hard-pinning/unpinning the pages. This will no longer be > the case with addition of memory shrinker because pages_use_count > 0 won't > determine anymore whether pages are hard-pinned (they will be soft-pinned), > while the new pages_pin_count will do the hard-pinning. Switch the > vmap/vunmap() to use pin/unpin() functions in a preparation of addition > of the memory shrinker support to drm-shmem. > > Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com> > --- > drivers/gpu/drm/drm_gem_shmem_helper.c | 19 ++++++++++++------- > include/drm/drm_gem_shmem_helper.h | 2 +- > 2 files changed, 13 insertions(+), 8 deletions(-) > > diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c > index d93ebfef20c7..899f655a65bb 100644 > --- a/drivers/gpu/drm/drm_gem_shmem_helper.c > +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c > @@ -257,6 +257,14 @@ static int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem) > return ret; > } > > +static void drm_gem_shmem_unpin_locked(struct drm_gem_shmem_object *shmem) > +{ > + dma_resv_assert_held(shmem->base.resv); > + > + if (refcount_dec_and_test(&shmem->pages_pin_count)) > + drm_gem_shmem_put_pages_locked(shmem); > +} > + > /** > * drm_gem_shmem_pin - Pin backing pages for a shmem GEM object > * @shmem: shmem GEM object > @@ -304,10 +312,7 @@ void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem) > return; > > dma_resv_lock(shmem->base.resv, NULL); > - > - if (refcount_dec_and_test(&shmem->pages_pin_count)) > - drm_gem_shmem_put_pages_locked(shmem); > - > + drm_gem_shmem_unpin_locked(shmem); > dma_resv_unlock(shmem->base.resv); > } > EXPORT_SYMBOL_GPL(drm_gem_shmem_unpin); > @@ -345,7 +350,7 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, > return 0; > } > > - ret = drm_gem_shmem_get_pages_locked(shmem); > + ret = drm_gem_shmem_pin_locked(shmem); > if (ret) > goto err_zero_use; > > @@ -368,7 +373,7 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, > > err_put_pages: > if (!obj->import_attach) > - drm_gem_shmem_put_pages_locked(shmem); > + drm_gem_shmem_unpin_locked(shmem); > err_zero_use: > shmem->vmap_use_count = 0; > > @@ -405,7 +410,7 @@ void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem, > return; > > vunmap(shmem->vaddr); > - drm_gem_shmem_put_pages_locked(shmem); > + drm_gem_shmem_unpin_locked(shmem); > } > > shmem->vaddr = NULL; > diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h > index bd545428a7ee..396958a98c34 100644 > --- a/include/drm/drm_gem_shmem_helper.h > +++ b/include/drm/drm_gem_shmem_helper.h > @@ -137,7 +137,7 @@ int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv); > static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem) > { > return (shmem->madv > 0) && > - !shmem->vmap_use_count && shmem->sgt && > + !refcount_read(&shmem->pages_pin_count) && shmem->sgt && > !shmem->base.dma_buf && !shmem->base.import_attach; > } >
diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index d93ebfef20c7..899f655a65bb 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -257,6 +257,14 @@ static int drm_gem_shmem_pin_locked(struct drm_gem_shmem_object *shmem) return ret; } +static void drm_gem_shmem_unpin_locked(struct drm_gem_shmem_object *shmem) +{ + dma_resv_assert_held(shmem->base.resv); + + if (refcount_dec_and_test(&shmem->pages_pin_count)) + drm_gem_shmem_put_pages_locked(shmem); +} + /** * drm_gem_shmem_pin - Pin backing pages for a shmem GEM object * @shmem: shmem GEM object @@ -304,10 +312,7 @@ void drm_gem_shmem_unpin(struct drm_gem_shmem_object *shmem) return; dma_resv_lock(shmem->base.resv, NULL); - - if (refcount_dec_and_test(&shmem->pages_pin_count)) - drm_gem_shmem_put_pages_locked(shmem); - + drm_gem_shmem_unpin_locked(shmem); dma_resv_unlock(shmem->base.resv); } EXPORT_SYMBOL_GPL(drm_gem_shmem_unpin); @@ -345,7 +350,7 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, return 0; } - ret = drm_gem_shmem_get_pages_locked(shmem); + ret = drm_gem_shmem_pin_locked(shmem); if (ret) goto err_zero_use; @@ -368,7 +373,7 @@ int drm_gem_shmem_vmap_locked(struct drm_gem_shmem_object *shmem, err_put_pages: if (!obj->import_attach) - drm_gem_shmem_put_pages_locked(shmem); + drm_gem_shmem_unpin_locked(shmem); err_zero_use: shmem->vmap_use_count = 0; @@ -405,7 +410,7 @@ void drm_gem_shmem_vunmap_locked(struct drm_gem_shmem_object *shmem, return; vunmap(shmem->vaddr); - drm_gem_shmem_put_pages_locked(shmem); + drm_gem_shmem_unpin_locked(shmem); } shmem->vaddr = NULL; diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index bd545428a7ee..396958a98c34 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -137,7 +137,7 @@ int drm_gem_shmem_madvise_locked(struct drm_gem_shmem_object *shmem, int madv); static inline bool drm_gem_shmem_is_purgeable(struct drm_gem_shmem_object *shmem) { return (shmem->madv > 0) && - !shmem->vmap_use_count && shmem->sgt && + !refcount_read(&shmem->pages_pin_count) && shmem->sgt && !shmem->base.dma_buf && !shmem->base.import_attach; }
The vmapped pages shall be pinned in memory and previously get/put_pages() were implicitly hard-pinning/unpinning the pages. This will no longer be the case with addition of memory shrinker because pages_use_count > 0 won't determine anymore whether pages are hard-pinned (they will be soft-pinned), while the new pages_pin_count will do the hard-pinning. Switch the vmap/vunmap() to use pin/unpin() functions in a preparation of addition of the memory shrinker support to drm-shmem. Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com> --- drivers/gpu/drm/drm_gem_shmem_helper.c | 19 ++++++++++++------- include/drm/drm_gem_shmem_helper.h | 2 +- 2 files changed, 13 insertions(+), 8 deletions(-)